3/4 written a decimal please show division

Find the value of tan theta if sin theta = 12/13 and theta is in quadrant 2

Achemist has 200 ml of a 10% sucrose solution. she adds x ml of a 40% sucrose solution. the percent concentration, y, of the final mixture is given by the rational function: the chemist needs the concentration of the final mixture to be 30%. how many milliliters of the 40% solution should she add to the 10% solution to get this concentration?

The border line of the linear inequality 4x + 7y < 5 is dotted true or false?